Collector Ouphe stops the activated abilities of artifacts, which shuts off Mox Opal, Seat of the Synod (an Artifact Land), Lotus Petal, Chrome Mox, and the Mishra's and Urza's Baubles, crippling their mana and card flow at once. It also stops Tormod's Crypt and Skateboard's equip. It does not stop Urza's Saga or Emry, Lurker of the Loch, since neither is an artifact, and it will also shut off our own Mox Diamonds. Prismatic Ending can exile cheap key permanents like Mox Opal or a Construct token using our two-color mana. We cut slow-grinding creatures that don't interact with their artifact-synergy plan, since this matchup is about denying their engine.